sump

noun \ ˈsəmp \

Updated on: 31 Mar 2018

Definition of sump

1 : a pit or reservoir serving as a drain or receptacle for liquids: such as

a : cesspool

b : a pit at the lowest point in a circulating or drainage system (such as the oil-circulating system of an internal combustion engine)

c chiefly British : oil pan

2 British : crankcase

[German Sumpf, literally, marsh, from Middle High German — more at swamp]

a : the lowest part of a mine shaft into which water drains

b : an excavation ahead of regular work in driving a mine tunnel or sinking a mine shaft

4 : something resembling a sump : sink 2

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Recent Examples of sump from the Web

The bottom of the tank farm is probably gravel with a liner below it and a low area or sump, said Tom DeRuyter, DEC's on-scene coordinator for the agency's northern region.

— zaz hollander, Anchorage Daily News, "Human error blamed for 22,000-gallon spill at Savoonga tank farm," 15 Mar. 2018
Breathable concrete was laid as the base, allowing water to seep through and be sucked up by sumps.

— tod leonard, sandiegouniontribune.com, "City golf awaiting approval for work on Torrey Pines South," 10 Oct. 2017
The Fox Lake seeped in, despite a new sump pit Evanson had jackhammered through the concrete floor slab.

— robert mccoppin, McHenry County, "Some homeowners have fought flooding for years," 21 July 2017
A more worrying issue was our car’s on-again, off-again oil consumption, as well as a dealer who, on at least one occasion, left the sump two quarts low after an oil and filter change.

— josh jacquot, Car and Driver, "2016 Chevrolet Camaro SS," 19 July 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sump.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.